Looking for cooling and air-circulation advice

U need to insulate that shed and put at least 12,000 btus worth of ac in there to keep the temps where you want. but i would just run like a 10" fan through air cooled lights. and set up air exchange for once a minute with a big 12". my rooms get warm in the summer ( up to 90 degrees) with no problems. although i do run c02

clean that ducting up so there arent any big loops. try to keep lengths short and straight for efficiency

to clarify the lights should get air from outside the room. then pass through the lights, sealed. and exhausted out the room. separate from this, you should have a large fan exhausting heat from the top of the room and a smaller fan blowing in cooler air from the bottom/underneath the shed. thus maintaining negative pressure

i would try to make that run of ducting you have as straight as possible too. all you would have to do is move the fan up about 2 feet. you would be suprised the cfm's your gonna lose with those 90 degree angles in the duct. A 90 degree bend is equal in pressure loss to 10 feet of duct. so that right there means it would be like having an extra 30 feet of duct. Simple fix and it will help cool your room way more efficiently.

So do you guys think 82-83 is too high for my max temp. the temps when the lights are off is about 66

one thing you can do that will give you at least 30% more air extraction, move your fan level with your exhaust hole going out, that bend right by the fan is slowing down your air movement a lot, and maybe try attaching to the front side of the lamp again, as few bends as possible in the ducting is the goal.

10* is about the max diff you want between lights on/off, much more than that and the plants will transpire and mess with humidity.

im not sure if anyne has touched on this or if you are already doing so, but run your lights at night too, that will drop temps a LOT! last room was runnin 8pm-8am and temps were really stable in a garage.

best of luck bud!

Ccoastal

Some plants can bud nicely in higher temp conditions and others with get fluffy lack resin and take forever to finish. In a perfect world i like to keep my canopy 80 or below but i can tolerate 85 and still get decent results. Sub aims for 74 but i think that is off to the side of the canopy. Of course it is much cheaper electricity wise to use huge fans rather than ac as much as possible. Good luck!